1. Field of the Invention
The present invention generally relates to data transmission and, more specifically, to fast and highly scalable quota-based weighted arbitration.
2. Description of the Related Art
In a system where multiple clients can transmit data over a single physical connection, transmission requests from those clients need to be arbitrated. One arbitration scheme involves a least recently used (LRU) arbitration technique, where a client that has less recently been selected to transmit data over the physical connection is given priority over a more recently selected client. In operation, each client in a system where the LRU arbitration technique is implemented is assigned a priority. When a particular client waiting to transmit data and having a higher priority than all other clients waiting to transmit data is selected, the priority of the selected client is set to a lowest priority. In such a fashion, a client that was most recently selected to transmit data has a lower priority than other clients in the system.
One drawback of the LRU arbitration technique is that the arbitration is biased toward clients that send large amounts of data. Such a bias is introduced because the selection of a client is based purely on how recently the client was selected to transmit data irrespective of the amount of data transmitted. Therefore, in a system implementing an LRU arbitration technique, clients that transmit large amounts of data per transmission request consume an overall higher amount of bandwidth on the physical connection than clients that transmit small amounts of data per transmission request. Such an imbalance can lead to unnecessary data transmission delays thus affecting the overall performance of the system.
Accordingly, what is needed in the art is a system for arbitrating more fairly between different clients waiting to transmit data over a physical connection based on the amount of data transmitted by each client.